RE: (corrected) Re: [EFM] RE: OAM Transport Proposal
At 03:55 PM 4/23/2002 -0700, Jonathan Thatcher wrote:
>I'm a bit confused by your append here an could use an explanation.
>When you say "First, Preamble handler is located in RS layer ( RS layer
>is strictly a part of PHY )
>which has the high-speed control interface ( common to MAC and above
>)," can you provide the reference in the existing standard to the high
>speed control interface that you are talking about utilizing? Do we need
>to change the MAC? Will this be referenced by the MIB? How?
Using David's slide in Sep2001: please look at the page 4 of
I refer the green line between management entity and MAC/RS,
"Pervasive access", which is not part of 802.3 standard.
>Also, you mention that "The second, the OAMiF will be mostly like
>implemented by SW/FW ( that's the main reason why people want to use it ? )
>the resulting latency would be unpredictable, while OAMiP detect
>indication will be handle by HW with predictable latency." What does
>"handled by HW" mean? What exactly is the system response to the reception
>of the preamble bits? This system response has no SW/FW component?
>| -----Original Message-----
>| From: Hiroshi Suzuki [mailto:hsuzuki@xxxxxxxxx]
>| Sent: Tuesday, April 23, 2002 10:09 AM
>| To: Roy Bynum
>| Cc: Booth, Bradley; 'firstname.lastname@example.org'; 'email@example.com'
>| Subject: Re: (corrected) Re: [EFM] RE: OAM Transport Proposal
>| At 09:51 AM 4/23/2002 -0500, Roy Bynum wrote:
>| >If I understand you correctly, given that there will always
>| be additional
>| >latency translating the MDIO/MDC frames into preamble
>| information, and
>| >then send the preamble, even without a standard frame, it
>| will not provide
>| >any advantage in greater responsiveness than OAMiF. If that
>| is the case,
>| >then there is no advantage to OAMiP under any circumstances.
>| If that is
>| >the case, why include it even as optional?
>| >Thank you,
>| >Roy Bynum
>| First, Preamble handler is located in RS layer ( RS layer is
>| strictly a
>| part of PHY )
>| which has the high-speed control interface ( common to MAC
>| and above ).
>| So the speed is not the issue. Refer the preamble proposals
>| presented in
>| last several meetings.
>| The second, the OAMiF will be mostly like implemented by SW/FW
>| ( that's the main reason why people want to use it ? )
>| the resulting latency would be unpredictable,
>| while OAMiP detect indication will be handle by HW with
>| predictable latency.
>| The third, and PHY fault indication / protection by MAC
>| control layer is
>| something like SONET protection handled by IP packets
>| which engineers never have used.
>| >At 06:59 AM 4/23/2002 -0700, Booth, Bradley wrote:
>| >>A management frame I described is that defined in Clause 22
>| as a MDIO/MDC
>| >>communication. If the preamble is filtered by the PHY,
>| then there has to be
>| >>some way to pass this preamble OAM information to the
>| management entity. In
>| >>802.3, this is done via MDIO/MDC (or management frames). A
>| management frame
>| >>takes over 25 us to be passed across the MDIO/MDC
>| interface. Unless the
>| >>intention is to have the PHY handle all OAM in preamble
>| without management
>| >>entity intervention, then the response to the OAM in
>| preamble will be
>| >>hampered by the MDIO/MDC interface.
>| >>Sent from my Blackberry...